Titan is 5
+ 1 Card for 7 | 8 damage and Momentum (Ignore all shields)
Arc Blade + Lightning Unupped is 5
+ 2 Cards for 5 Spell Damage.
Fulgora + Lightning Upped is 4
+ 2 Cards for 8 Spell Damage.
IMHO you should lower the upped's starting attack to 5 and raise the unupped 'growth' rate to 2.